Mining machine



June 24, 1930.

C; E'. DAVIS MINING MACHINE 6 Sheets-Sheet Original Filed 001'.. 30, 1922 C. E. DAVIS MINING MACHINE June 24, 1930.

Original Filed OCT.. 30. 1922 6 SheetS-Shee 2 ffl-ffl. 7%;

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C. E. DAVIS MINING MACHINE June 24, 1930.

Original Filed Oct. 50. 1922 6 Sheets-Sheet 4 Inni;

June 24, 1930 c. E. DAVIS*l MINING MACHINE Original Filed Oct. 30. 1922 6 Sheets-Sheet jfmzia: Ca/Pk@ @a1/a1 .l mig June 24, 1930. C E, DAVIS 1,765,524

MINING MACHINE f Original Filed Oct. 50, 1922 6 Sheets-Sheet 6 Patented June 24, 1930 UNITED STAT/es N PATENT t ica CHARLES n. Devis, F ciIcAGo, ILLINors, Ass'renon. To eoonivrnn MANUFACTJNG Liners, A CORPORATION or rLtrN'oIs MINING MACHINE Application fried-,esatti 30,- 1922, serial No. 597,722. Renewed May 2, 192e.

This invention relates to improvements in mining machines and has for its principal object to provide a new and improved device of this description, which is capable of being quickly and easily handled during Clt ment and the device may further be arrangedv so that the controlling connection does not support the machine while the machine is cutting, the cutting elementy being sup*- ported upon the iioor of the mine and being freeV to follow any unevenness of the floor,

said cutting element' during the cutting? F movement,y independent of any vertically acting support. This contro-lling connection may thus be used to lift the cutting element and carry it t'o tlie point of use and lower it to the floor and then the lifting action may cease and the cutti'ng element be' supported on the floor, thus giving it great freedom of moveiiie'nt so that it may cut around stones and other hard'- obstacles instead of cutting through them and may follow the tloo'r of the mine whatever its forni7 shape,l contour -or' arrangement may be. A; machine ofthe type described permits the' cutting element separate from a i'nai-n frame or trucktol be handled' as though it were on the truclrand yet makes it unnecessary to unload;- it from the truck when being operated or loaditon the truck when being carried from point to point.v

In the mining machine disclosed in my prior application above referred to, `thecontrolling-l connection between thel nia-in traine;

and the, cuttingelement includes a pa'ir iol. controlling arms having their-rear .ends pivotally connected to the main frame at opopsite sides thereof and diverg'ingtherefrom to pivotal connections on opposite sides of the cutting element. This construction provides a modifiedl pantograph movement adapted to control the angular positions of the cutter arm with respect to the main traine in a peculiar manner particularly adapted for use in cutting relatively narrow entries. In the present invention, means are further provided for shifting the positionl ci these controlling arms whereby under certain conditions, as for instance when cutting relatively wide rooms7 this pantograph movement may be dispensed with and the controlling arms willV main-tain the cutter arm in a radial Aposition with respect to the axis Vof the controlling connection; Other features of improvement will' appear in the following specication from time to time as the description proceeds;

I have illustrated one form or" my invention wherein- Figure l is a plan view of the machine with the cutter bar at the forward end' removed.

c Fig. 2 is a side elevation of the machine sh'ovvnv in Figure l.

Figure 3 is a side view oi" a portion ol." the machine illustrating the mechanism for raising and lowering the cutting element.

Figure et is a sectional 'View ta'len on line 4-lof Figure 2. y

Figure si is a Yragmentary plan view showing how the anchor plate may be locked to the moving frame. I y

Figure 5 is a sectional view taken on line 5 5 of 'Figure l, butV drawn on af somewhat larger scale than Figure 4L'.-

Figure 6 isa sectional view' taken on line 6-6l of Figure l. l

'Figures 7 and 8 are details of the eccentric mechanism for adjusting the' angular` positien of the cutter bar withl relation to the Figure 9 is a sectional view taken on line 9 9 of Figure 6. n A

Figure l0 is a sectional view taken cn linelOlO of Figure 6; y n

Figure ll is a sectional view taken on line ll-ll of Figure l.

Figure 12 is a sectional vie'v taken on line 12H12 of Figure 1.

Figure 13 is a sectional view 1 3-13 of Figure 1.

Figure 14 is a sectional view taken on line 14-14 of Figure 1.

Figure 15 is a diagrammatic view showing the arrangement of the controlling arms in one position While making a sumping cut in a narrow room or entry.

Figure 1G is a diagrammatic view showing the machine aft-er the lateral cut has been made with the parts in position to make the tinal out.

Figure 17 is a diagrammatic View of the machine making a slabbing cut along one side of the track.

Figure 18 is a diagrammatic vieu1 shoiving the arrangement of the controlling arms preparatory to making a sumping cut in a Wide room.

Figure 19 is a view similar to Figure 16, but lWith the machine in Vposition after the sumping cut has been completed and positioned to maire a lateral swinging cut.

In carrying out my invention, 1 provide a taken on line machine having a main -frame 1 mountedv upon wheels 2. A movable frame 3 is supported on the main trarne 1 and arranged for pivotal swinging movement abouta hub L1 Which tits in a projection 5 on the trame 3 as best shown in Figure 5. The cutting element indicated at 10 is movably supported with respect to the main body of the machine by means of a pair of supporting arms 11, 11 (see Figs. 1, 2 and 3) arranged so that the outing element may be moved vertically into various positions. The 'supporting arms are connected at opposite endsto a transverse rock shaft 12 pivotally mounted between supports 13, 13 carried on the moving trame 5%. A rearwardly extending roel;- iug arm 1li is connected to one e d of the shaft 12.

The rocking arm 11 may be actuated by any suitable mechanism to raise or l'ower the supporting arms 11, 11 and the cutting element carried thereby. In the present instance, this mechanismincludes a gear .seg-

ment 15 on the end of arm 1st which cooperates with a gear segment 16 mounted on a lbearing 17. Asrock arm itl-is operatively connected to move with the gear segment- 16 and is adapted to be rocked by a link 19 eccentrically connected toa rotating gear 20, Vas best shown in Figures 2 and 3.

Said linlr 1s provided with a slot 21 in Which a pin 22 on the gear 20 is'engaged. The gear20 may be rotatd in any suitable mannenas for in-v stance, by means of a spur 23 and worm gear 24 having operative connection with a vworm 25. Said Worin is loosely mounted on longitudinal shaft 26 and is provided with suitable tlnust collars 25a, 25a, bearing between upright supports 25", 25", asl shown in shown is an electric motor Wiich is reversi-Y ble, so that When the clutch 27 is engaged, the gear 2O may be rotated in either direction to raise or lower the `elevating mechanism as desired. rEhe provision or the slot 1 in the linlr 19 permits the cutting element 'to be raised independently of the elevating mechanism When said element is in conta t With the ground and passes over raisedor rolling portions of the mine door.` Under such conditions, the linlr slidesl freely along the pin 22 so as to secure this result.

In the position shown in ull lines in Figures 2' and 8, the elevating mechanism is shown in position to permit the cutting element 10 to restr on the mine licor, With 'the pin 22 on the gear 20 at the outermost end ofthe slot 21 in the link 19. lll/Then it is desired to raise the cutting element, as for instance, to a position shown on' dotted lines in Fig. 3, the gear 2O is rotated in a clockwise direction so as to move the link 19 and arm 18 forwardly', thereby rocking tie gear segments 16 and 15 and arm 111 downwardly. This movement causes the forward ends of the arms 11, 11 to be raised as shown. The

cutting element may thus be reise-d from the ground to be swung laterally into any desired position, as for instance, when it is desired to swing the cutterr arm over the mine tracks.A

The forward ends of the supporting arms 11, 11 are shown split and clamped on the ends 36, 36 of the rod 34 on the cutting element. The ends 36, 86 are eccentric With the body portion 35 of the rods, said body portion having bearing in a pair 'of `bearing members V38, 38, carried' upon a transverse bracket?. The cutting element is provided with a cutter arm 9,and this eccentric construction ot the rod 34 is for the purpose of adjusting the cutter arm by raisor vloivering.its outer end so that its longitudinal airis may bemade parallel with the lio-or in the various positions ot the cutting element. lflfhen, for example,the arms 11, 11, areraised or lowered, this movement tends to move the `cutter arm so that it will the bracket l37 which is mounted on a lon--.

gitudinally extending pin 10 supported on the casing li1 of the cutting element 10. The

ico

of any suitable 'form land is herein shown asa chain 19 (see F ig. 1) mounted inthe usual manner on the cutter arms A`9. 4This cutter 'chain is driven in the following Inanner: A 'cutter chain 4sprocket -50 is mounted on 'an `upright shaft '51 ournaled in a ve'rtically disposed stud 52. This stud is in turn journaled in the 'casing 41 ofthe cutting element 10, and is integral with a laterally projecting 'member :53 "to which the cutter 'bar 9 is 'secured Vby suitable means such as bolts 541, 54. lThis construction is best shown in Figure 6. A `bevel jge'a'r 55 is mounted at the upper end of 't'heshaft 51 and is meshed with 'a horizontally `disposed bevel pinion 56 on the `shaft 57 which JeX- tends rearwardly 'through the casing 41 of the cutting element 10. An operative connection between the shaft l57 and shaft 62 mounted on a bearing'63 'at thefior-ward end of the moving frame 3, 'is afforded by va pair 'of suitable flexible connecting couplings 60, 60 of any ordinaryforin and a connecting shaft 51. The 'flexible couplings 60, 60 afford y'a driving connection 'between 'the actuating mechanism on themoving frame 3 andthe cutter chain in all 'permissible positions 'of the cutting element. The 'shaft 62 is driven 4by gear 64which is meshed'w'it'h la gear Vloosely vmounted-on Ashaft 26. (Sv'ee Figs. 11 and 13.) A 'clutch 0n the gear 65 is adapted to be operatively 'connected `to said shaft by a sliding clutch r'member 66. The shaft 26 is operatively connected 4to "the motor 30 as 'hereinbe'fore described bygear 28 and 'pinion'.29. The cutter chain 40 may thus be connected or disconnected a't 'will by means of the sliding clutch 66.

The cutting element is fed laterally tothe coal by means of a cable 70 on a drum 71 (see Figs. 1, 2,76 and 15 to 19). This cable is fastened "to a suitable jack or anchor, ar-

ranged in various positions desired, as shown in Figures 13 to 17. In thepresent instance, the drum 77 is rotatably mounted about the stud 52 and is actuated by the following mechanism: A gear 72 keyed on the shaft f is meshed with a gear 73 loosely mounted on shaft 7el'which is vconcentric with the shaft 62. A gear pinion 75 is mounted 'to rotate with gear 73 and yis mesh'ed with a gear 76 loosely mounted on shaft 77. 'Y (See Figs. 11, 13 and rlhe gear76-is keyed on a hub 78 on which is carried a sun gear 79 forming a part ofthe planetary 'transmission device 80. This planetary fdevice may be of any ordinary form and has driven member 81 keyed 'to a sleevel 'which in turn is 'keyed to the shaft 77 .v This sleeve is associated with one member Aof a slip clutch,'as will hereinafter be more fully described. A =miter gear 9.0 is carried on fthe forwardlend of the shaft'77 Land is engaged with a miter :gear 91 v-on a transverse lshaft 92. A `Ichain sprocket 93 is keyed on :the shaft v92 and isconn'ected by a chain '94 to a chain ysprocket 95 mountedVon one side ofthe casing 11 ofthe cutting element 10 (see iFig. 1). A'bevel gear196 ismounted 'to rotate with the sprocket 95 and is meshed with a bevel gear rotatably 'mounted on the drum 71. The bevel lgear 97 is operatively connected to the drum 71 'by means of a "ratchet device of any ordinary form, sueh as a pawl 98 adapted fto engage in one or more 'notches 99,99 spacedabout the upper barrel ofthe drum (see Fig. 9). 'By means of the operating connections just described, the cable may be wound vu'pon the drum at a lreduced. `speed suitable :for feeding the cutter chain Vto "theeoal. When it'is desired to wind the 'cable on `rthe drum by hand, the pawl 98 vis released and Ithe drum 71 is :then free to be rotated `-by any suitable means, such as a bar inserted in apertures 100, 100 formed at Yintervals 'about the lower periphery of said drum. `The cable 70 lis trained about suitable sets of sheaves 110, 1111, V1.12, mounted on `opposite sides of the projecting arm 53 so that the cable may be extended from 'the 'cuttingelement in either direction as desired.

The moving vframe 3 is swung laterally by the following mec'hanism': The main iframe 1 ispirovided at the rear end 'thereof with 'a rack 121. `("See Figs. 1, 2 and l.) This rackis engafge'dA by a pinion 122 mounted 'on the underside of the moving V'frame 3. This pinion is preferably driven from the 'motor'. Saidpinio'n 122 is 'meshed with anii'l'ler pinion 123 which in turn is 'meshcd with a pin ion 124: on shaft 125. A bevel pinion 126 mounted on 'the'upper end 'of sa'idshlaft land is meshed with a bevel pinion 127 loosely mounted on a longitudinal shaft 128 as 'best shown lin 'Figure 112. y l

In 'th'econstruetion illustrated in r`Figures 1, 12, 13 and 14, it will be seen'that the bevel pinion 127 may be driven either at l'highmlow speed, as desired. rlhe low speed connection is as follows: A gear 129 is keyed on vsha-'ft 128 and may Ehave drivingengage- Inen't with 't'lie'pinion 127 through a sliding clutch 133 feathered on said shaft. 129 is meshed l with gear 130 loosely mounted on shaft 132. Gear 130 is adapted to have driving engagement with said shaft through a clutch member 134 feathered on the latter. A slip clutch member 131 is keyed on shaft 132 and is mounted to rotate with a casing 8a, forming one member of the slip clutch, as shown. The other member, 822fof this 'clutch 'comp-rises a friction plate integral Gear L with the sleeve 82. The members are hold in frictional engagement by a. plurality of springs 85, 85. The tension of the springs may be regulated by a loclr nut 83, threaded ou the end of sleeve 82. The slip clutch is driven through the planetary gear mechanism 80, reducing gears .75 and 76, gear 73 and the driving mechanism connecterL with the motor 30, as hereinbefore described. It will thus be seen that the moving frame 3 may be rotated at relatively slow speed by gearing which may now be traced as follows Vgear 73 through gears 75 and 7 3, planetary device 80, slip clutch members 31, 82 and 131, shaft 132, clutch member 134, gears and 129, shaft 128, clutch 133, bevel gears 127 and 126 shaft 125 and pini-ons 124, 123, 122 to rack 121.

Then rotating fra ie 3 in this manner,

the pawl 98 (see Figures 6 and 9) is pref-V erably thrown out of engagement so that drum 71 will not be driven.

Power connections are also provided for rotating 'the moving frame at vhigh speed which connections are as follows: A sliding gear is mounted on the longitudinal shaft 74 as shown in Figure 13. The gear 135 is shifted laterally by means of a suitable clutch collar 161, and is provided with a clutch member 136 adapted tobe moved into engagement with clutch member 137 carried by a bevel pinion Y138 loosely mounted on the shaft 74. The gear 135 is meshed withgear 139 loosely mounted on shaft 132. The gear 139 is in turn meshed with gear keyed on the shaft 128. The shaft 74 is driven through clutch 74a and gear 73. 1t will, therefore, be noted that shafts 74 anc 132 are both driven from this last named gear 73, but the shaft 74 will be driven at a relatively greater speed owing to its direct connection with this gear. The high speed connection may now be traced Vas follows: from shaft 74 through vclutch 137, gears 135, 139 and 160, clutch 133, bevel pinions 123 and 127, shaft 125 and pinions 124, 123, and 122 to rack 121.

The power connections just described for swinging the moving frame 3 are primarily for the purpose of positioning the moving frame 3 and the cutting element V10 preparatory to the cuttino operation. uring the cutting operation the cutting elementY is preferably moved bythe draft rope 70 as indicated inthe diagrams shown in Figures 15 to 17. Therefore', during the cutting operation, clutch 133 is ldisengaged and the frame swinging mechanism is in operation. Under some conditions, however, it maybe desirable to feed the cutting element to the coal by means of the power connections for swinging the moving frame 3, as for Vinstance, the low speed connections may be used for this purpose.

The operation of the gearing mechanism just described also provides high and low speed connections for propelling the machine bodily along the mine trac-lr. One pair of wheels 2, 2, are mounted on a shaft 176 and have driving connections with stud shaft 171 through gears 177 and 178. The

other pair of wheels 2, 2, are mounted on shaft 179 and have driving connections with stub shaft 172 by a chain 180 and chain sprockets 181, 182. Stub shafts 171 and 172 are mounted on the main frame and are driven through miter gears 173, 174 which mesh with miter gear 17 5 on the shaft 170. A bevel gear 183 is mounted on shaft 170 which extends Vconcentrically through. the. iub 4 on which the moving frame 3 swings, so as to permit the wheels to be driven in all positions of the swinging frame 3 as is best shown in Figure 5.

The bevel speed connection to bevel driving gear 183 is provided through gears 73, 75 76, planetary gear 80, slip clutch members 8 1, 82 and 131shaft 132, sliding clutch 134, gears 139 and 135, clutch members 136 and 137, and bevel pinion 138.

he bevel driving gear 133 is driven at high speed through gear 73, clutch 7 4a, shatt 74 and pinion 138.

1n order to control the angular position of the cutting element with respect to the moving frame 3 as the latter is rotated on its axis, a pair of controlling arms 140, 140, are pivotally connected on opposite sides Of an annular ring 141, loosely mounted on stud 52 of the cutting element 10. The cutter arm 9 is adapted to be locked with respect to the ring 141 by suitable means such as a locking pin 53a projecting through the member 53 and adapted to fit in one of a plurality vof holes 53b depending uponfthe position of the cutter arm. It' will thus be seen that the locking pin 53-A may be removed and the cutter arm swung around in any desired angle on either side of the straight forward position. The parts are arranged so the cutter arm can be moved through an angle of approximately degrees. The controlling arms 140, V140, are each hinged intermediate their ends on pivots 142, 142 and extend rearwardly between the moving frame 3 and 'main frame 1, where they are pivotally connected on pins 144, 144, mounted on opposite sides of an anchor plate 145. This anchor plate is mounted to rotate about an annular flange145a extending upwardly fromfthe main frame 1 and is best shown in Figures 4 and 5. The anchor plate Vmay be fixed with respect to the main frame 1 by any suitable means, as for instance, a locking pin V143 may be vfitted in an aperture 147 as in said plate and a. registering aperture 143 in the main frame 1. In the forni illustrated, these apertures are accessible through an opening 149 formed in the moving frame 3, when the latter is in the position as shown iff/.65,524

in Figure 1. When the anchor plate 145 is fixed with respectv to the-mainframe 1the movement of the cutter arm is controlledas illustrated in Figures 15' and-16m which the machine is shown asworking in a narrow entry. On. Figure 15, it willfbe seen.y that the moving frame 3 isswung to the. right with respect4 to the main frame l. Owing to the position ofl pins y144, 144, which are held rigidly on. opposite sides of the longitudinal axis off the main frame 1, and the divergence of the controlling, arms,.the cutter bar 9 is. swung into a slightly deflected position at a smalli angle to the right rib or wall of the entry. The. cutter' arm-is thus held in a desirable position for lmaking its sumping out along the right ribwhen the machine is moved forwardly ask shown. This controlling action. of the arms 1.40 140 is in effect a modified pantograph movement similar to that disclosedinmy prior appli.- cation bearing Serial No. 444,767, filed February 14, 1921, .hereinheforerefer-redto, in which the cutter arm is inclined outwardly when it is on. opposite. sides of the straight forward position of the cutting element but in the latter. positionis'in longitudinal alignment with the main frame 1. In Figure 16 the position of the cutter arm is shown at the end of the cut,y that is to say, after the cutten arm hasl beenv swung laterally across the face. In this position it will be seen that the cutter arm is inclined outwardly to the left. and away from the longitudinal axis of the main frame in position to be easily withdrawn when the machine is moved outwardly on the mine track. When it is desired to swing the moving frame 3 and the cutter arm 9` about a common axis, the anchor. plate is released from its. rigid connection with the main frame 1, and is locked with respect to the moving frame 3 by means of a locking pin 150 whichv is inserted through an aperture 151 in the moving frame 3 into locking engagement with an aperture 152 in the'anchon.

plate 145. When the anchor plate-.145 is thus locked tofthe moving frame 3, the controlling arms 140,140are maintained rigidly; with respect to said moving, frame'so that no pantograph movement` similar to that.v

illustrated in` Figuresl and-16 occurs, but the controllingl arms swingy angularly with the moving frame. The cutter arm 9 is locked as before in position with respect to the ring 141 and the controlling arms 140, 140. The machine is then sumped with. the cutter bar 9 in longitudinal alignment with' the movement frame 3, and thereafter swung about a common axis with said frame 3 to cut a kerf as indicated in dotted lines in Figure 19.

The machine may also be used for making a slabbing cut, that is to say, the cutter arm may be locked in position to extend laterally from the machine andthe entire machine movedbodily along the mine track as shown in Figure. 17. In this position` of the cutter arm, the anchor. plate may be fixed withrelation to the main. frame 1 as shown. in this figure, or itV may be fixed rigidlywith relationA to the moving frame 3, as desired.

Then the machine is being trans-ported from place to place, the moving frame 3 mayy be rigidlylocked withV respect tothe main frame 1 by utilizing both locking pins 146 and 1504 in the anchor frame, thereby securing all the parts against lateral movement. on the main; frame.

I claim as my invention:l

1. In: a mining machine, a base frame, a movingV frame, a swinging; cutting element forward of said moving frame including. a cutter arm and a support therefor, two separated-arms pivotally connected at' their forwarde endsy with said cutter arm-support andr so connected at their rear' ends to both thebase andswinging frames asto be movable horizontallyl withy respectto either, and means affording afi'xed connection for the rear ends' of said arms either with respect to said base frame on said moving. frame.

2. In a mining machine, a base frame, a moving frame, al swinging cutting element forward of said moving frame, including a cutter arml and7 a support therefore, two separated arms pivotally connected: attheir forwandends with said; cutter arm.y support and connecting means for theA rear. ends of. said varms adjustable angularly with: respect to said base frame.

3; In amining. machine, a base frame, a moving frame pivotally connected with said base frame, a swinging cutting element forward of said moving frame, including a cutter: arm and a` support therefor, two

separatedl arms pivotally connected at thein forward. ends with saidl cutter arm support, connecting means for the rear ends of said armsrotatably mounted concentric with the axis of` said moving frame, and means for lockingv said connecting; means either with respectto said base frame or said# moving frame.

4. In aA mining machine, a: base frame, a movingv frame pivotally connected thereto on a vertical. axis, aV swinging cutting element forward: of: said moving frame, including a, cutter arm. andv` a' support .therefor, two separated arms pivotallyconnected. atV their. forwardy endsswith said cutter armv rsupport and so connected at their rear ends to both` the base andy moving frames. as to be movable withv respect to either, means affording a fixed connection for the rean ends of said arms` either with. respect to said base, frame or said. moving. frame, and. supporting means carried by said moving. frame-independent.. of said. arms for. lifting and lowering said' cutting* element.

5. In a mining machine, a base frame, a moving frame pivotally connected thereto on a vertical axis, a swinging cutting element forward of said moving frame, including a cutter arm and a support therefor, two separated arms pivotally connected at their forward ends with said cutter arm support and so connected at their rear ends to both the base and moving frames as to be movable with respect to either, means affording a fixed connection for the rear ends of said arms either with respect to said base frame or said moving frame, supporting means carried by said moving frame independent of said arms for lifting and lowering said cutting element, and power devices for positioning said'inoving frame angularly respective to said base frame.

6. In a mining machine, a base frame, a movable frame ,pivotally connected thereto on a vertical axis, a swinging cutting element forward of said moving` frame, including a cutter arm and a support therefor, two separated arms pivotally connected at their forward ends with said c 'ttor arm support and so connected at their rear ends to both the base and moving frames as to be movable with respect to either, means affording a fixed connection for the rear ends of said arms either with resp-oct to said base frame or said moving frame, supporting means carried by said moving frame independent of said arms for lifting and lowering said cutting element, power devices for positioning said moving frame angularly respective to said base frame, and other power devices including flexible draft means adapted to coact with said cutting element to feed the cutter to the coal.

7. In a mining machine, a base frame, a moving frame pivotally connected with said base frame, a swinging cutting element forward of said moving frame including a cutter arm and a. support therefor, two separated arms pivotally Connected at their foi'- ward ends with said cutter arm support and so connected at their rear ends to both the base and moving frames as to be movable with respect to either, connecting means for the rear ends of said arms rotatably mounted concentric with the axis of said. moving frame, means locking said connecting means either with respect to said base frame or said moving frame, ann supporting means carried by said moving frame independent of said arms for lifting and lowering said Cutting element. Y

8. In a mining machine, a base frame, a moving frame, a swinging cutting element forward of said moving frame, two sepa-y rated arms pivotally connected at their forward end-s with said cutting element, connecting means for the rear ends of said arms' rotatably mounted concentric with the axis of said moving frame, means locking said connecting means either with respect to said base frame or said moving frame, supporting means carried by said moving frame independent of said arms for lifting and lowering said cutting element and power devices for positioning said moving frame angularly respective to said base frame.

9. In a mining machine, a base frame, a moving frame, a swinging cutting element forward of said moving frame, two separated arms pivotally connected at their forward ends with said cutting element, connecting means for the rear ends of said arms rotatably mounted concentric with the axis of said moving frame, means locking said connecting means either with respect to said base frame or said moving frame, supporting means carriedby said moving frame independent of said arms for lifting and lowering said cutting element, power devices for positioning said moving frame angularly respective to said base frame,'and other power devices including flexible draft means adapted tov coact with said cutting element to feed the latter to the coal. Y

l0. In a mining machine, a base frame, a moving frame pivotally connected thereto on a vertical axis, a swinging cutting element forward of said moving frame, two separated arms pivotailyconnected at their forward ends with said cutting element' and so connected at their rear ends to both the f base and moving framesas to be movable with respect to either, said arms being more widely separated at their forward than at their rear ends, and means affording a fixed connection for the rear ends of said arms either witl respect to said base frame or said moving frame.

1l. In a miningv machine, a base frame, a moving frame, a Vswinging cutting element forward of said moving frame, two separated arms pivotally connected at their forward ends with said cutting element, said arms being more widely separated at their forward than at their' rear ends, connecting means for the rear ends of said arms rotatably mounted concentric with the axis of said moving frame and means locking said connecting means either with respect to said base frame or said moving frame.

Signed at Chicago, in the county of Cock and State of Illinois, this 27th day of October, 1922;

CHARLES E. DAVIS. 

